Method of using vasoconstrictive agents during energy-based tissue therapy

ABSTRACT

A mammal undergoing an energy-based therapy is treated by administering at least one vasoconstrictive agent to the mammal prior to or during the procedure. The at least one vasoconstrictive agent is added in amounts sufficient to reduce or prevent vasodilation. This treatment method increases or promotes the size of the coagulation zone created after energy-based therapy.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. Pat. No. 8,968,234filed on Jun. 1, 2012, which is a continuation of U.S. Pat. No.8,202,242 filed Jul. 16, 2008, which is a divisional of U.S. patentapplication Ser. No. 11/487,223 filed Jul. 14, 2006, now abandoned,which is a continuation-in-part of U.S. Pat. No. 7,767,686, filed Mar.3, 2006, the entire contents of each of which are hereby incorporated byreference.

BACKGROUND

1. Technical Field

The present disclosure relates to application of vasoconstrictive agentsfor use during the energy-based tissue therapies or procedures and, morespecifically, to a treatment regimen that prevents or alleviatessymptoms associated with vasodilation.

2. Background of the Related Art

Energy-based tissue therapies such as ablation techniques are usedclinically and in the operating room for therapeutic and surgicalpurposes. Such techniques eliminate tissue using energy sources such aslaser, microwave, radiofrequency, high-intensity focused ultrasound,cryotherapy (such as freezing below −20 C), conductive heating, and thelike. Although energy-based therapies such as tissue ablation therapiesand procedures have been successful in treating patients, thesetherapies and procedures are problematic in that they can lead toelevated concentrations of the purine nucleoside adenosine in treatedareas. Adenosine can be problematic and counterproductive to theenergy-based therapy and/or overall treatment. For example, adenosinecan promote metastasis disease, angiogenesis, tumor cell proliferation,vasodilation, cardiac depression, low blood pressure, and otherdetrimental symptoms such as metastatic bloom. Moreover, adenosine caninhibit cell-mediated anti-tumor immune response. Vasodilation may beproblematic during an energy-based therapy in that, among other things,it may reduce the size of the coagulation zone formed during anenergy-based procedure.

SUMMARY

The present disclosure relates to a method of treating symptomsassociated with adenosine including the step of administering to amammalian subject undergoing an ablation procedure at least one agent inan amount effective in preventing or alleviating at least one symptomassociated with an elevated concentration of adenosine in the mammaliansubject. The agent may be at least one adenosine receptor antagonistsuch as 8SPT, MRS1754, MRS1220, MRE3008F20, MRS1523, ATL146e, orcombinations of these adenosine receptor antagonists. In embodiments,the agent binds to at least one adenosine receptor in vivo.

In one embodiment, the agent is administered for the treatment ofsymptoms associated with adenosine such as inhibition of cell-mediatedanti-tumor immune response, metastasis disease, angiogenesis, tumor cellproliferation, vasodilation, cardiac depression, low blood pressure, andcombinations of these symptoms or conditions.

In another embodiment, the agent can be administered for the treatmentor prevention of low blood pressure, and/or prevention of metastasisdisease. The ablation procedure may be an energy-based tissue ablation.

The agent may be at least one A1 adenosine receptor antagonist,including but not limited to: 1,3-dipropyl-8-cyclopentylxanthine,8-(4-[({[(2-aminoethyl)amino]carbonyl)oxy]-phenyl}-1,3-dipropylxanthine,N(6)-Endonorbornan-2-yl-9-methyladenine,((S)-(−)-8-(3-Oxocyclopentyl)-1,3-dipropyl-7H-purine-2,6-dione),(3-[(4-amino)phenethyl]-8-cyclopentylexanthine,1,3-dipropyl-8-(dicyclopropylmethyl)xanthine, and combinations of theseadenosine receptor antagonists.

In another embodiment, the agent may be at least one A2 adenosinereceptor antagonist, including but not limited to:1,3-diallyl-8-(3,4,5-trim ethoxystyryl)-7-methylxanthine,8-(3,4,5-trimethoxystyryl)-1,3,7-trimethylxanthine,7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine,4-(2-[7-amino-2-(2-furyl[1,2,4]-triazolo[2,3-a[1,3,5]triazin-5-yl-)phenol), 8-(3-Chlorostyryl)caffeine,E)-1,3-dipropyl-7-methyl-8-(3,4-dimethoxystyryl)xanthine, enprofylline,3-isobutyl-8-pyrrolidinoxanthine,[N-(4-cyanophenyl)-2-[4-(2,3,6,7-tetrahydro-2,6-dioxo-1,3-dipropyl-1H-purin-8-yl)-phenoxy]acetamide],and combinations of these adenosine receptor antagonists.

In yet another embodiment, the agent is at least one A3 adenosinereceptor antagonist, including but not limited to:3,6-dichloro-2′-(isopropoxy)4′-methylflavone,6-phenyl-1,4-dihydropyridines,6-carboxy-methyl-5,9-dihydro-9-methyl-2-phenyl-[1,2,4]-triazolo[5,1-a][2,7]naphthyridine,(3-(4-methoxyphenyl)-5-amino-7-oxo-thiazolo[3,2]pyrimidine),9-chloro-2-(2-furanyl)[1,2,4]triazolo[1,5-c]quinazolin-5-amine,(2-(4-bromophenyl)-7,8-dihydro-4-propyl-1H-imidazo[2,1-i]purin-5(4H)-onedihydrochloride), and combinations of these adenosine receptorantagonists. The agent may be administered in a pharmaceuticalcomposition which includes a pharmaceutically acceptable carrier ordiluent.

The present disclosure further relates to a method of treating symptomsassociated with adenosine comprising the step of administering to amammalian subject undergoing an ablation procedure at least oneadenosine receptor antagonist in an amount effective in preventing oralleviating at least one symptom associated with adenosine. In someembodiments, the adenosine receptor antagonist includes 8SPT, MRS1754,MRS1220, MRE3008F20, MRS1523, ATL146e, or combinations of theseadenosine receptor antagonists.

The present disclosure further relates to a method of treating symptomsassociated with adenosine comprising the step of administering to amammalian subject undergoing an ablation procedure at least oneadenosine receptor antagonist in an amount effective in preventing oralleviating at least one symptom associated with adenosine, wherein theadenosine receptor antagonist includes 8SPT, MRS1754, MRS1220,MRE3008F20, MRS1523, ATL146e, or combinations of these adenosinereceptor antagonists. In some embodiments, the ablation procedure is aradiofrequency ablation of a cancer tumor.

The present disclosure further relates to an ablation method includingthe step of administering to a mammalian subject undergoing an ablationprocedure at least one adenosine receptor antagonist in an amounteffective to prevent or minimize vasodilation associated with anelevated concentration of adenosine in the mammalian subject. Theablation procedure produces a coagulation zone having a radius thatranges from a length of about 1 cm to about 20 cm.

In some embodiments, the present disclosure relates to an ablationmethod including the step of administering to a mammalian subjectundergoing an ablation procedure at least one adenosine receptorantagonist in an amount effective to prevent or minimize vasodilationassociated with an elevated concentration of adenosine in the mammaliansubject, wherein the at least one adenosine receptor antagonistcomprises 8SPT, MRS1754, MRS1220, MRE3008F20, MRS1523, ATL146e, orcombinations thereof. The adenosine receptor antagonist may beadministered in a pharmaceutical composition that includes apharmaceutically acceptable carrier or diluent. The ablation may be anenergy-based tissue ablation, including but not limited to radiofrequency energy-based tissue ablation.

The present disclosure further relates to a method of treating symptomsassociated with adenosine including the step of administering to amammalian subject undergoing an ablation procedure at least oneadenosine receptor antagonist in an amount effective in preventing oralleviating vasodilation associated with adenosine. The adenosinereceptor antagonist may be 8SPT, MRS1754, MRS1220, MRE3008F20, MRS1523,ATL146e, or combinations thereof.

The present disclosure further relates to an ablation method of treatingvasodilation comprising administering to a mammalian subject undergoingan ablation procedure at least one adenosine receptor antagonist in anamount effective in preventing or alleviating vasodilation. Theadenosine receptor antagonists may include, but are not limited to,aminophylline, 8SPT, MRS1754, MRS1220, MRE3008F20, MRS1523, ATL146e, andcombinations thereof. The ablation method may be a radiofrequencyablation of a cancer tumor. The cancer tumor may be located in theliver, kidney and/or lung.

The present disclosure further relates to a method of promoting the sizeof a coagulation zone formed during radiofrequency ablation procedureincluding, but not limited to the following step: administeringadenosine antagonist to a patient; and ablating tissue in need thereof.

The present disclosure further relates to a method of preventing oreliminating vasodilation during a radiofrequency procedure including,but not limited to the following step: administering to a patient inneed thereof an amount of adenosine receptor antagonist effective inpreventing or reducing vasodilation due to adenosine.

The present disclosure further relates to a surgical technique includingthe steps of: administering at least one vasoconstrictive agent to apatient; and performing an energy-based therapy to form a coagulationzone. In some embodiments, the step of performing an energy-basedtherapy further comprises ablating tissue. In some embodiments, theenergy-based therapy includes cardiac ablation, transmyocardialrevascularization, benign prostate hyperplasia therapy, ablation ofendometriosis, breast cancer treatment, hemostasis, vessel sealing,endometrial ablation, skin resurfacing, metastasis ablation,image-guided treatments, noninvasive blood flow monitoring, surgicaltissue welding, tissue reshaping, laser therapy, microwave therapy,radiofrequency therapy, high-intensity focused ultrasound therapy,cryotherapy therapy, conductive heating, and/or combinations thereof.

DETAILED DESCRIPTION

Adenosine is a purine nucleoside compound having the general formula:

Adenosine or 9-B-D-ribofuranosyl-9H-purin-6-amine is prevalentthroughout the body, and functions in various biochemical pathways byinteracting with adenosine receptors that detect local changes inadenosine concentration.

The term “receptor” refers to a macromolecule capable of recognizing andselectively binding with a ligand and, after binding with the ligand, iscapable of generating a physical or chemical signal that initiates thechain of events leading to the physiological response. Adenosinereceptors are proteins found in animals and humans that can bind theligand, adenosine, causing a physiological response. Adenosine receptorshave been located in a variety of tissues and cells, includinghippocampus, adipocytes, atrioventricle node, striatum, platelets,neutrophils, coronary vasculature and olfactory tubercule.

Four adenosine receptors are commonly referred to as A1, A2A, A2B, andA3. The stimulation of A1 receptors, among other things, can inhibitnerve cells, lower heart rate, slow AV nodal conduction, and promotevasoconstriction. The stimulation of A2A receptors is generallyanti-inflammatory, and can be used to sense excessive tissueinflammation, and promote coronary vasodilation. The stimulation of A2Bgenerally promotes vasodilation. The stimulation of A3 receptors, amongother things, can both stimulate and inhibit cell growth, and promotetumor growth and angiogenesis.

Ligands that bind to the adenosine receptor causing the inhibition ofthe adenosine receptor physiological response are termed adenosinereceptor antagonists. Likewise, ligands that bind to the adenosinereceptor, thereby generating a physiological response that mimics theresponse caused by the adenosine receptor binding adenosine, are termedadenosine receptor agonists.

During energy-based ablation procedures or therapies inflamed or damagedtissues can release adenine nucleotides that are converted to the purinenucleoside adenosine. The degradation of extracellular nucleotidesresults in an elevated concentration of adenosine in the treated area,which can be problematic and counterproductive to the therapy ortreatment. Accordingly, as used herein, an elevated concentration ofadenosine in the mammalian subject refers to any increase in adenosineconcentration in a mammalian body, including but not limited to anyincrease of adenosine concentration in one or more organs, tissues,systems, blood or blood parts, plasma, or the like. Moreover, anelevated concentration of adenosine in the mammalian subject refers toany higher than normal accumulation of adenosine that can detrimentallypromote metastasis disease, angiogenesis, tumor cell proliferation,vasodilation, cardiac depression, low blood pressure, and combinationsof these detrimental symptoms, or which can inhibit cell-mediatedanti-tumor immune response.

The present disclosure relates to methods for treating or alleviatingsymptoms associated with adenosine by administering to a mammaliansubject undergoing an ablation procedure at least one agent in an amounteffective in preventing or alleviating the symptoms associated withadenosine. As used herein the word “treat,” “treating” or “treatment”refers to using the active agents or compositions of the presentdisclosure either prophylactically to prevent undesirable adenosinesymptoms, or therapeutically to ameliorate an existing undesirablecondition caused by adenosine. Treatment regimens in accordance with thepresent disclosure improve symptoms associated with adenosine throughapplication of pre-selected antagonists to at least one adenosinereceptor.

These methods are based upon the recognition that the inhibition of theadenosine receptor physiological response prior to or during an ablationprocedure provides beneficial effects that prevent or reduceangiogenesis, tumor cell proliferation, vasodilation, cardiacdepression, and/or low blood pressure. Furthermore, the inhibition ofthe adenosine receptor physiological response prior to or during anablation procedure prevents or reduces likelihood of metastasis disease,or the limiting effect of adenosine on cell-mediated anti-tumor immuneresponse. Blocking of adenosine receptors maximizes the desiredprotective benefits, while minimizing unwanted side effects from thestimulation of adenosine receptors, such as heart block, cardiacdepression, or low blood pressure. Therefore, methods and compounds aredescribed that can promote blocking of adenosine receptors. Moreover,the methods are based upon the recognition that the inhibition of thevasodilation prior to or during an energy-based therapy providesbeneficial effects such as the chemical occlusions of blood perfusion orthe degree that blood flows to the treatment site.

In some embodiments, deactivation of the adenosine receptor occurs bycontacting any adenosine receptor with at least one adenosineantagonist. Non-limiting examples of suitable adenosine antagonistsinclude aminophylline, MRS 1754, MRS1220, MRE3008F20, MRS1523, ATL146e,either alone or in combination. Other receptor antagonist fall withinthe scope of the present disclosure including, but not limited to thoseadenosine antagonists listed in Table 1. Moreover, non-selectiveadenosine antagonists, such as 8-(p-sulfophenyl)theophylline (8SPT) canalso be used in accordance with the present disclosure.

The adenosine receptor antagonists can be administered in amountssuitable to obtain the desired affect. For example, at least oneadenosine receptor antagonist may be supplied in amounts sufficient toreduce or eliminate detrimental symptoms of adenosine, such asmetastasis disease, angiogenesis, tumor cell proliferation,vasodilation, cardiac depression, low blood pressure, and combinationsof these detrimental symptoms. Moreover, adenosine receptor antagonistscan be administered in amounts suitable to prevent inhibition ofcell-mediated anti-tumor immune responses caused by adenosine. In someembodiments, adenosine receptor antagonists can be supplied in an amountfrom about 0.1 to 200 nmol/min/kg.

However, the specific dose level for any particular individual maydepend on a variety of factors: including the activity of the specificcompound employed, the age, body weight, general health, sex and diet ofthe individual being treated; the time and route of administration; therate of excretion; other drugs that have previously been administered;and the severity of the particular disease undergoing therapy.

The adenosine receptor antagonists can be administered during anyprocedure or therapy that increases the amount of adenosine in amammalian body. Illustrative non-limiting examples of such procedures ortherapies include energy-based tissue ablation such as cardiac ablation,transmyocardial revascularization, benign prostate hyperplasia therapy,ablation of endometriosis, breast cancer treatment, hemostasis, vesselsealing, endometrial ablation, skin resurfacing, metastasis ablation,image-guided treatments, noninvasive blood flow monitoring, surgicaltissue welding, tissue reshaping, radiofrequency thermal ablation orradiofrequency ablation (RFA) (suitable for use in bone, and softtissues such as liver, kidney, lung, heart, breast, lymph nodes, andnerve ganglia).

In accordance with the present disclosure, the compounds may beadministered by a variety of means including orally, parenterally, byinhalation spray, topically, or rectally in formulations containingpharmaceutically acceptable carriers, adjuvants and vehicles. The termparenteral as used here includes subcutaneous, intravenous,intramuscular, and intraarterial injections with a variety of infusiontechniques. Intraarterial and intravenous injection including perfusionand administration through catheters can be suitable. In someembodiments, methods of administration that allow rapid access to thetissue or organ being treated, such as intravenous injections for thetreatment of myocardial infarction, is suitable. When an organ outside abody is being treated, perfusion can be a suitable method ofadministration.

Pharmaceutical compositions containing the active ingredient can be inany form suitable for the intended method of administration, includingtablets, troches, lozenges, aqueous or oil suspensions, dispersiblepowders or granules, emulsions, hard or soft capsules, syrups orelixirs. Compositions intended for oral use can be prepared according toany method known to the art for the manufacture of pharmaceuticalcompositions. Tablets containing the active agent in admixture withnon-toxic pharmaceutically acceptable excipients that are suitable formanufacture of tablets are acceptable.

Formulations for oral use can include hard gelatin capsules where theactive ingredient is mixed with an inert solid diluent, or as softgelatin capsules wherein the active ingredient is mixed with water or anoil medium.

The pharmaceutical compositions in accordance with the presentdisclosure can be in the form of a sterile injectable preparation, suchas a sterile injectable suspension. This suspension may be formulatedaccording to the known art using those suitable dispersing or wettingagents and suspending agents. In some embodiments, the sterileinjectable preparation can also be a sterile injectable solution orsuspension in a non-toxic parenterally acceptable diluent or solvent.Among the acceptable vehicles and solvents that may be employed arewater, Ringer's solution and isotonic sodium chloride solution. Inaddition, suitable sterile fixed oils may be employed as a solvent orsuspending medium.

The amount of active ingredient that may be combined with the carriermaterial to produce a single dosage form may vary depending upon thehost treated and the particular mode of administration. For example, atime-release formulation intended for oral administration to humans maycontain 20 to 200 μmoles of active material compounded with anappropriate and convenient amount of carrier material, which may varyfrom about 5 to about 95% of the total composition. In some embodiments,pharmaceutical composition can be prepared that provides easilymeasurable amounts for administration. For example, an aqueous solutionintended for intravenous infusion should contain from about 20 to about50 μ.moles of the active ingredient per milliliter of solution in orderthat infusion of a suitable volume at a rate of about 30 mL/hr canoccur.

Formulations of the present disclosure suitable for oral administrationmay be presented as discrete units, such as: capsules, cachets ortablets, each containing a predetermined amount of the activeingredient; as a powder or granules; as a solution or a suspension in anaqueous or non-aqueous liquid; or as an oil-in-water liquid emulsion ora water-in-oil liquid emulsion. The active ingredient may also beadministered as a bolus, electuary or paste.

A tablet may be made by compression or molding, optionally with at leastone accessory ingredient. Compressed tablets may be prepared bycompressing in a suitable machine the active ingredient in a freeflowing form, such as a powder or granules, optionally mixed with abinder, surface active or dispersing agent. Molded tablets may be madeby molding in a suitable machine a mixture of the powdered compoundmoistened with an inert liquid diluent. The tablets may optionally becoated or scored and may be formulated so as to provide slow orcontrolled release of the active ingredient therein. Tablets mayoptionally be provided with an enteric coating, to provide release inparts of the gut other than the stomach.

Formulations for rectal administration may be presented as a suppositorywith a suitable base.

Formulations suitable for vaginal administration may be presented aspessaries, tampons, creams, gels, pastes, foams or spray formulationscontaining in addition to the active ingredient such carriers as areknown in the art to be appropriate.

Formulations suitable for parenteral administration include aqueous andnon-aqueous isotonic sterile injection solutions, which can be made inaccordance with techniques known in the art. The formulations can bepresented in unit-dose or multi-dose sealed containers, for example,ampoules and vials, and may be sorted in a freeze-dried (lyophilized)condition requiring only the addition of the sterile liquid carrier, forexample water for injections, immediately prior to use. Extemporaneousinjection solutions and suspensions may be prepared from sterilepowders, granules and tablets of the kind previously described.

In some embodiments, suitable unit dosage formulations are thosecontaining a daily dose or unit, daily sub-dose, or an appropriatefraction thereof, of an adenosine receptor antagonist compound.

In some particular embodiments, therapies have been developed to reduceor minimize vasodilation caused by, for example, an excess and/orelevated amount of adenosine, such as any increase in adenosineconcentration in a mammalian body, including but not limited to anyincrease of adenosine concentration in one or more organs, including thekidneys, lungs, and/or liver, tissues, systems, blood or blood parts,plasma, or the like. An elevated concentration of adenosine in themammalian subject further refers to any higher than normal accumulationof adenosine that can detrimentally promote vasodilation and/or bloodflow induced cooling.

Adenosine accumulation is problematic for it acts as a local vasodilatorand a local regulator of blood flow. Reducing or minimizing vasodilationnear a tumor, promotes the formation of a coagulation zone during anenergy-based therapy. Accordingly, treatments are now available forminimizing and or preventing vasodilation, as well as increasing thesize of the coagulation zone formed during an energy-based therapy suchas an RF ablation procedure.

Accordingly, the present disclosure relates to methods for treating,preventing and/or alleviating vasodilation such as that caused byelevated adenosine. These goals may be obtained by administering to amammalian subject undergoing an energy-based procedure at least onevasoconstrictive agent in an amount effective in preventing oralleviating vasodilation. Accordingly, “treat,” “treating” or“treatment” further refers to using the active agents or compositions ofthe present disclosure either prophylactically to prevent vasodilation,or therapeutically to ameliorate existing vasodilation such as thatcaused by adenosine. As used herein, “vasodilation” refers to relaxationor opening of at least one blood vessel. Treatment regimens inaccordance with the present disclosure reduce vasodilation throughapplication of pre-selected vasoconstrictive agents such as antagoniststo at least one adenosine receptor.

These methods are based upon the recognition that the inhibition of anadenosine receptor physiological response such as vasodilation prior toor during an ablation procedure provides beneficial effects that preventor reduce vasodilation and/or increase the size of the coagulation zone.Blocking of adenosine receptors maximizes the desired protectivebenefits, while minimizing unwanted side effects. Therefore, methods andcompounds are described that can promote blocking of adenosinereceptors.

In some embodiments, vasodilation is prevented, reduced and/oreliminated at the energy-based therapy target tissue site byadministering to the patient a vasoconstrictive agent in amountsufficient to reduce blood flow in or near the energy-based therapytarget tissue site. For example, a vasoconstrictive agent may besupplied in amounts sufficient to chemically occlude blood perfusion inand around the therapy target tissue site. Suitable non-limitingexamples of vasoconstrictive agents include sympathomimetic amines,sympathomimetic vasopressins, adrenaline, nor-adrenalin, levonordefrin,nordefrin, phenylphrine, and combinations thereof. Additionalnon-limiting examples of vasoconstrictive agents include adenosinereceptor antagonists as described herein.

The vasoconstrictive agent can be administered before, or during anyenergy-based therapy such as those therapies that cause an increasedblood flow in or near the target tissue site. Illustrative non-limitingexamples of such procedures or therapies include energy-based tissueablation such as cardiac ablation, transmyocardial revascularization,benign prostate hyperplasia therapy, ablation of endometriosis, breastcancer treatment, hemostasis, vessel sealing, endometrial ablation, skinresurfacing, metastasis ablation, image-guided treatments, noninvasiveblood flow monitoring, surgical tissue welding, tissue reshaping,radiofrequency thermal ablation or radiofrequency ablation (RFA)(suitable for use in bone, and soft tissues such as liver, kidney, lung,heart, breast, lymph nodes, and nerve ganglia), laser therapy, microwavetherapy, radiofrequency therapy, high-intensity focused ultrasoundtherapy, cryotherapy therapy, conductive heating, or combinationsthereof.

In some embodiments for preventing or minimizing vasodilation,deactivation of the adenosine receptor(s) that promote vasodilationoccurs by contacting any adenosine receptor with at least one adenosineantagonist. Any adenosine receptor blocker that inhibits vasodilationdue to the expression of adenosine can be used. Non-limiting examples ofsuitable adenosine antagonists include aminophylline, MRS 1754, MRS1220,MRE3008F20, MRS1523, ATL146e, either alone or in combination. Otherreceptor antagonist fall within the scope of the present disclosureincluding, but not limited to those adenosine antagonists listed inTable 1. Moreover, non-selective adenosine antagonists, such as8-(p-sulfophenyl)theophylline (8SPT) can also be used in accordance withthe present disclosure.

The adenosine receptor antagonists can be administered in amountssuitable to obtain the desired affect. For example, at least oneadenosine receptor antagonist may be supplied in amounts sufficient toprevent and/or minimize vasodilation. In some embodiments for preventingand/or minimizing vasodilation, adenosine receptor antagonists can besupplied in an amount from about 0.1 to 200 nmol/min/kg.

The adenosine receptor antagonists can be administered during anyprocedure or therapy where vasoconstriction is desirable. Illustrativenon-limiting examples of such procedures or therapies includeenergy-based tissue ablation such as cardiac ablation, transmyocardialrevascularization, benign prostate hyperplasia therapy, ablation ofendometriosis, breast cancer treatment, hemostasis, vessel sealing,endometrial ablation, skin resurfacing, metastasis ablation,image-guided treatments, noninvasive blood flow monitoring, surgicaltissue welding, tissue reshaping, radiofrequency thermal ablation orradiofrequency ablation (RFA) (suitable for use in bone, and softtissues such as liver, kidney, lung, heart, breast, lymph nodes, andnerve ganglia), laser therapy, microwave therapy, radiofrequencytherapy, high-intensity focused ultrasound therapy, cryotherapy therapy,conductive heating, or combinations thereof.

The present disclosure further relates to a method for increasing thesize of a coagulation zone formed during energy-based tissue ablation.Energy-based ablation therapy can be applied to tissue having a tumor.Generally, such procedures heat and kill the tissue by coagulationinduced cell death. For example, a coagulation zone may be formed afterheating liver tissue with an RF electrode. Such liver tissue may have acoagulation zone having a radius X. Radius X is obtained by measuringalong the cross-section of the thickest portion of the tissue, and isequal to the length from center of the cross-sectional cut to the outerperimeter of the cut. In state-of-the-art procedures, radius X may beabout 0.5 cm to about 3.5 cm. Accordingly, the coagulation zone may havea diameter of about 1 cm to about 7 cm. Surrounding coagulation zone maybe a hyperemic rim, which is typically a zone of increased blood flow asa result of vasodilation.

As another example, a coagulation zone may be formed after heating withan RF electrode and administrating at least one vasoconstrictive agentsuch as adenosine receptor antagonist in an amount effective to preventor minimize local vasodilation. The liver tissue may have a coagulationzone having a radius Y. Radius Y is obtained by measuring along thecross-section of the thickest portion of the tissue, and is equal to thelength from center of the cross-sectional cut to the outer perimeter ofthe cut. Radius Y may be about 1 cm to about 10 cm. Accordingly, thecoagulation zone may have a diameter of about 2 cm to about 20 cm.Surrounding coagulation zone may be hyperemic rim. Here, hyperemic rimmay be narrower than hyperemic rim described above, due to the reducedvasodilation caused by the administration of at least one adenosinereceptor antagonist in an amount effective to prevent or minimize localvasodilation. Moreover, coagulation zone may be larger than the priormentioned coagulation zone due to the administration of at least oneadenosine receptor antagonist in an amount effective to prevent orminimize local vasodilation in the liver.

TABLE 1 (Some A1, A2 and A3 receptor antagonists) Abbreviation ChemicalName A1 ANTAGONISTS DPCPX 1,3-dipropyl-8-cyclopentylxanthine XAC8-(4-[({[(2-aminoethyl)amino]carbonyl)oxy]-phenyl}-1,3- dipropylxanthineN-0861 N(6)-Endonorbornan-2-yl-9-methyladenine KFM 19((S)-(−)-8-(3-Oxocyclopentyl)-1,3-dipropyl-7H-purine- 2,6-dione)BW-A844U (3-[(4-amino)phenethyl]-8-cyclopentylexanthine KF 153721,3-dipropyl-8-(dicyclopropylmethyl)xanthine A2 ANTAGONISTS (SubtypesA2A and A2B) DATSX 1,3-diallyl-8-(3,4,5-trimethoxystyryl)-7-methylxanthine DM TSX8-(3,4,5-trimethoxystyryl)-1,3,7-trimethylxanthine SCH 582617-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-triazolo[1,5-c] pyrimidine ZM 2413854-(2-[7-amino-2-(2-furyl[1,2,4]-triazolo[2,3-a[1,3,5]triazin-5-yl-)phenol) CSC 8-(3-Chlorostyryl)caffeine KF17837E)-1,3-dipropyl-7-methyl-8-(3,4-dimethoxystyryl)xanthine Enprofylline3,7-Dihydro-3-propyl-1H-purine-2,6-dione IPDX3-isobutyl-8-pyrrolidinoxanthine MRS 1754[N-(4-cyanophenyl)-2-[4-(2,3,6,7-tetrahydro-2,6-dioxo-1,3-dipropyl-1H-purin-8-yl)-phenoxy]acetamide] A3 ANTAGONISTS MRS 10673,6-dichloro-2′-(isopropoxy)4′-methylflavone MRS 10976-phenyl-1,4-dihydropyridines L-249313 6-carboxy-methyl-5,9-dihydro-9-methyl-2-phenyl-[1,2,4]- triazolo [5,1-a][2,7]naphthyridineL-268605 (3-(4-methoxyphenyl)-5-amino-7-oxo-thiazolo [3,2]pyrimidine)CGS15943 9-chloro-2-(2-furanyl)[1,2,4]triazolo[1,5-c]quinazolin-5- amineKF26777 (2-(4-bromophenyl)-7,8-dihydro-4-propyl-1H-imidazo[2,1-i]purin-5(4H)-one dihydrochloride)

The following examples are given for the purpose of illustrating thepresent disclosure and are not intended to limit the scope in any way.

EXAMPLE I

A 65 year old female weighing 130 pounds with liver tumor is undergoingRF ablation of 5 cm tumor located in liver. During the RF ablation thepatient is simultaneously administered adenosine receptor antagonist inan amount sufficient to, in vivo, block A1, A2, A3 adenosine receptorsimmediately adjacent to the tumor. The ablation step is performed bydelivering electrical current of about 500 kHz between the electrode anda ground pad. Tissue is heated by, among other things, thermalconduction. The temperature of the tissue depends upon, among otherthings, thermal and electrical tissue properties, and blood perfusion.Her liver is a well perfused organ with perfusion rates of around 1L/kg/min (with tumor having a lower perfusion rate). By blocking theadenosine receptors immediately adjacent to the tumor, localvasodilation adjacent to the tumor is prevented. The hyperemic rim isreduced and the coagulation zone increased in size compared to a similarprocedure without adenosine receptor antagonist administered to thepatient.

EXAMPLE II

A 60 year old male weighing 155 pounds with liver tumor is undergoingenergy-based therapy of 6 cm tumor located in liver. During theenergy-based therapy the patient is simultaneously administered at leastone vasoconstrictive agent in an amount sufficient to reduce blood flowin and immediately adjacent to the tumor. The energy-based therapy isperformed by delivering electrical current of about 500 kHz between theelectrode and a ground pad. Tissue is heated by, among other things,thermal conduction. The temperature of the tissue depends upon, amongother things, thermal and electrical tissue properties, and bloodperfusion. His liver is a well perfused organ with perfusion rates ofaround 1 L/kg/min (with tumor having a lower perfusion rate).Vasodilation in and around the tumor is prevented. The hyperemic rim isreduced and the coagulation zone increased in size compared to a similarprocedure without vasoconstrictive agent administered to the patient.

While several embodiments of the disclosure are described, it is notintended that the disclosure be limited thereto, as it is intended thatthe disclosure be as broad in scope as the art will allow and that thespecification be read likewise. Therefore, the above description shouldnot be construed as limiting, but merely as exemplifications ofembodiments. Those skilled in the art will envision other modificationswithin the scope and spirit of the claims appended hereto.

What is claimed is:
 1. A surgical technique comprising: administering atleast one A2 adenosine receptor antagonist to a patient; and performingan energy-based therapy to form a coagulation zone.
 2. A surgicaltechnique in accordance with claim 1, wherein the step of performing anenergy-based therapy further comprises ablating tissue.
 3. A surgicaltechnique in accordance with claim 1, wherein the energy-based therapycomprises cardiac ablation, transmyocardial revascularization, benignprostate hyperplasia therapy, ablation of endometriosis, breast cancertreatment, hemostasis, vessel sealing, endometrial ablation, skinresurfacing, metastasis ablation, image-guided treatments, noninvasiveblood flow monitoring, surgical tissue welding, tissue reshaping, lasertherapy, microwave therapy, radiofrequency therapy, high-intensityfocused ultrasound therapy, cryotherapy therapy, conductive heating, orcombinations thereof.
 4. A surgical technique in accordance with claim1, wherein the coagulation zone is formed after heating with an RFelectrode and administrating at least one adenosine receptor antagonist.5. A surgical technique in accordance with claim 1, wherein the energybased therapy produces a coagulation zone having a radius.
 6. A surgicaltechnique in accordance with claim 5, wherein the radius has a length ofabout 1 cm to about 10 cm.
 7. A surgical technique in accordance withclaim 1, wherein the coagulation zone has a diameter of about 2 cm toabout 20 cm.
 8. A surgical technique in accordance with claim 1, whereinthe at least one A2 adenosine receptor antagonist is administered in anamount effective to prevent or minimize local vasodilation.
 9. Asurgical technique in accordance with claim 1, wherein the at least oneA2 adenosine receptor antagonist is administered simultaneously toperforming the energy-based therapy in an amount effective to prevent orminimize local vasodilation.
 10. A surgical technique in accordance withclaim 1, wherein the at least one A2 adenosine receptor antagonist isadministered prior to performing the energy-based therapy in an amounteffective to prevent or minimize local vasodilation.
 11. A surgicaltechnique in accordance with claim 1, wherein in vivo, the at least oneA2 adenosine receptor antagonist binds to at least one adenosinereceptor.
 12. A surgical technique in accordance with claim 1, whereinthe at least one A2 adenosine receptor antagonist is administered in apharmaceutical composition that includes a pharmaceutically acceptablecarrier or diluent.
 13. A surgical technique in accordance with claim 1,wherein the at least one A2 adenosine receptor antagonist is selectedfrom the group consisting of 1,3-diallyl-8- (3,4,5-trimethoxystyryl)-7-methylxanthine,8-(3,4,5-trimethoxystyryl)-1,3,7-trimethylxanthine,7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine,4-(2-[7-amino-2-(2-furyl[1,2,4]-triazolo[2,3-a[1,3,5]triazin-5-yl-)phenol), 8-(3-Chlorostyryl)caffeine,E)-1,3-dipropyl-7-methyl-8-(3,4-dimethoxystyryl)xanthine, enprofylline,3-isobutyl-8-pyrrolidinoxanthine, [N-(4-cyanophenyl)-2-[4-(2,3,6,7-tetrahydro-2,6-dioxo-1,3-dipropyl-1H-purin-8-yl)-phenoxy]acetamide],and combinations thereof.
 14. A surgical technique in accordance withclaim 1, further comprising administering at least one of MRS 1754,MRS1220, MRE3008F20, MRS1523, ATL146e, 8SPT in combination with the atleast one A2 adenosine receptor antagonist.
 15. A surgical technique inaccordance with claim 1, wherein the administering step includestreatment of symptoms associated with adenosine including tumor cellproliferation.
 16. A surgical technique in accordance with claim 1,wherein the administering step includes administering the adenosinereceptor antagonist immediately adjacent to tissue being treated.
 17. Asurgical technique in accordance with claim 1, wherein the at least oneA2 adenosine receptor antagonist is administered in an amount from about0.1 to about 200 nmol/min/kg.
 18. A surgical technique in accordancewith claim 1, further comprising administering at least one A1 adenosinereceptor antagonist in combination with the at least one A2 adenosinereceptor antagonist.
 19. A surgical technique in accordance with claim1, further comprising administering at least one A3 adenosine receptorantagonist in combination with the at least one A2 adenosine receptorantagonist.
 20. A method for promoting blocking of an adenosine receptorin a mammalian subject undergoing an energy-based ablation procedure byadministering at least one A2 adenosine receptor antagonist to themammalian subject.